At nine, against his father's wishes, he entered and easily won a race in his home town, the prize for which included a training scholarship.

[8] Alongside mountain biking, Bernal had begun to gain success in junior road racing both in Colombia and Italy, winning the Clasica Juventudes Cajica[9] and the Sognando Il Giro delle Fiandre[10] in 2015.

Bernal was signed by Gianni Savio to the Androni Giocattoli–Sidermec team on a four-year contract, partly on the evidence of a VO2 max reading of 88.8ml/kg/min provided by his agent, Paolo Alberati.

[13] He later finished third overall in the Settimana Internazionale di Coppi e Bartali, second in the Giro dell'Appennino, and ninth in the Tour of the Alps.

[18] Bernal's next race was the Volta a Catalunya, in which he was second on general classification when he fell on a wet descent in the final stage, fracturing his clavicle and scapula.

[19][20] The following month, Bernal competed in the Tour de Romandie, winning stage three of the race, an individual time trial[21] and finishing second overall behind Primož Roglič.

[22][23] In July, he rode the Tour de France as a domestique for team leaders Chris Froome and Geraint Thomas.

The Colombian impressed in the crosswinds, the individual time trial, and in the mountains, claiming the overall victory ahead of Nairo Quintana.

Bernal next finished third in the Volta a Catalunya, and was scheduled to lead Team Ineos at the Giro d'Italia until he broke a collarbone in a training injury in Andorra.

Bernal was elevated to be co-leader of the team with defending champion Thomas for the Tour de France, because of the absence through injury of Froome.

[36] On the final mountain stage, Caruso and his teammate Pello Bilbao distanced Bernal on the descent of the San Bernardino Pass 50 km from the finish in pursuit of a group of riders from Team DSM including Bardet before working with riders from an earlier breakaway to extend their lead over Bernal to 50 seconds up the penultimate climb of the Splügen Pass.

[37] Bernal secured the pink jersey on the final time trial in Milan, conceding another 30 seconds to Caruso to win by a one and a half minute margin.

[38] He became the fourth rider to win both the Tour and the Giro before reaching the age of 25, after Gino Bartali, Felice Gimondi and Eddy Merckx, and also the fourth rider to win both the overall and youth classifications in the same Giro, alongside Evgeni Berzin, countryman Nairo Quintana and teammate Tao Geoghegan Hart.

[39] Bernal entered the 2021 Vuelta a España with a very strong team that also included Richard Carapaz and Adam Yates.

On a training ride in Gachancipá with Ineos Grenadiers teammates on the 24 January, Bernal hit the back of a stopped passenger bus at a speed of about 50 kilometres per hour (31 mph).

[42] In total, doctors counted 20 separate fractures and initially warned there was a 95% chance Bernal would die or be paralyzed.

[45] He began to recover quickly, and by early March was sharing his progress with friends, family and fans on social media.